U.S. patent application number 12/007428 was filed with the patent office on 2008-07-24 for arrangement at telescopic lifting beams.
Invention is credited to Gunnar Liljedahl.
Application Number | 20080173853 12/007428 |
Document ID | / |
Family ID | 38616841 |
Filed Date | 2008-07-24 |
United States Patent
Application |
20080173853 |
Kind Code |
A1 |
Liljedahl; Gunnar |
July 24, 2008 |
Arrangement at telescopic lifting beams
Abstract
A lifting means includes at least two telescopically
displaceable lifting beams (1, 2), of which one (2) is connected to
a driving means (3) in order to displace the second lifting beam
(1) to and fro within said first lifting beam. A casing (4) can be
placed to surround both the lifting beams and rest against these
and surrounds both the lifting beams an essential part when they
are protruded. A pressure spring (5) is placed within the casing
(4) in order to displace the casing (4) so it surrounds both the
lifting arms (1, 2) when they are in the protruded position in
relation to each other whereby the pressure spring rests against
the end of the casing (4), which end surrounds the displaceable
lifting arm (1). A support (6) for the second end of the pressure
spring (5) is attached on the fixed lifting beam (2).
Inventors: |
Liljedahl; Gunnar; (Lulea,
SE) |
Correspondence
Address: |
JACOBSON HOLMAN PLLC
400 SEVENTH STREET N.W., SUITE 600
WASHINGTON
DC
20004
US
|
Family ID: |
38616841 |
Appl. No.: |
12/007428 |
Filed: |
January 10, 2008 |
Current U.S.
Class: |
254/89R |
Current CPC
Class: |
B66F 3/28 20130101 |
Class at
Publication: |
254/89.R |
International
Class: |
B66F 19/00 20060101
B66F019/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 19, 2007 |
SE |
0700121-7 |
Claims
1. Arrangement at a lifting means consisting of at least two
telescopically displaceable lifting arms, of which one is connected
to a driving means in order to displace the second lifting beam to
and fro within the first lifting beam, whereby a casing can be
brought to surround both the lifting beams and being extended a
certain distance over both the lifting beams in their protruded
position, characterized in that a pressure spring (5) is situated
within the casing (4) and rests against the casing (4) at the end,
which surrounds the displaceable lifting arm (1) and that a support
(6) is attached on the fixed lifting arm (2) for supporting the
second end of the pressure spring, which support (6) has a distance
from the end of the lifting beam (2), which distance corresponds to
about half of the length of the casing (4).
2. Arrangement according to claim 1, characterized in that the end
of the casing (4) which faces the driving means (3), includes a
ring (8), which slides against the outside of the lifting beam (2)
and that a corresponding support (7) is arranged at the second end
of the casing and forms the support for the end of the pressure
spring (5).
3. Arrangement according to claim 2, characterized in that the
support (7) at the second end of the casing is in the form of a
cover (7).
Description
[0001] This invention relates to an arrangement at least two
telescopically protrudable lifting beams, of which one is connected
to a driving means in order to displace the second beam to-and-fro
in said first beam, whereby a casing can be brought to surround
both beams resting on them and extending a long part of the
beams.
[0002] Lifting beams of this type are used, e.g. within the medical
service for lifting means, when a person is being lifted from a
sitting position to a standing position or from one place to
another. Telescopic lifting beams of this kind are also used for
other lifting purposes for patients.
[0003] The lifting beams are normally loaded in their longitudinal
direction and they are designed to meet such a load. The lifting
beams can be driven hydraulically via gears or manually using
rope-driving means or with the help of a crank means.
[0004] It has now shown, e.g. within the medical service, that the
lifting beams unintentionally have been loaded by bending when the
telescopic beams are in their protruded position in relation to
each other, which have lead to that the outer lifting beam has been
bent in the area where it protrudes out of the outer end of the
first lifting beam. The object of the invention is to increase the
strength of the lifting beams when they are in their protruded
position and that this is accomplished by simple means, which are
cheap. SE 516855 discloses such a solution consisting of a casing,
which can be displaced on the beams so it covers e.g. half of the
fixed beam and the first half of the protrudable beam so that the
casing also takes up the bending stresses.
[0005] The object of the invention is to simplify the design of the
means, which perform the displacement of the casing when the
movable beam is protruded for carrying out its lifting movement.
The characteristics of the invention are stated in the following
claim 1.
[0006] An embodiment of the invention will now be described by
reference to the drawings.
[0007] FIG. 1 is hereby a partly longitudinal cross section of the
lifting arrangement, having both lifting arms in retracted
position.
[0008] FIG. 2 is a partly longitudinal cross section as in FIG. 1,
but the movable lifting arms are in protruded position.
[0009] FIG. 3 is an enlarged cross section at the position a in
FIG. 1.
[0010] FIG. 4 is an enlarged part of the cross section at position
B in FIG. 2.
[0011] FIG. 5 is a part of an enlarged cross section at position C
in FIG. 2.
[0012] The arrangement shown in FIGS. 1 and 2 comprises a lifting
beam 1, which is telescoping in a second lifting beam 2, being
fixed to a driving means 3 which displaces the first lifting beam
1. The driving means 3 can be any known engine as e.g. an hydraulic
engine or a gear motor, which drives the lifting beam 1 telescoping
in the lifting beam 2. The lifting beams are loaded when the
lifting beam 1 is protruding out of the lifting beam 2 in the
position shown in FIG. 2. As can be seen from FIG. 2, the lifting
beams 1 and 2 are surrounded by a telescopic pipe or casing 4,
which is displaceable over the two lifting beams 1 and 2. FIG. 1
shows the position of the lifting beams in which the telescopic
casing 4 is completely displaced downwards over the fixed lifting
beam 2. FIG. 2 shows the telescopic casing 4 being placed over the
half length of the lifting beam 1 and over the half length of the
lifting beam 2.
[0013] The displacement of the telescopic casing 4 from the
position shown in FIG. 1 to the position shown in FIG. 2 is
performed by a pressure spring 5 which is located within the
lifting beam 2. The telescopic casing 4 can also be said to be a
case or casing. The end of the pressure spring 5 which faces the
driving means 3 rests on a support 6 which is attached about on the
middle of the lifting arm 2. The second end of the pressure spring
3 is supported by a cover 7 on the upper end of the telescoping
casing 4. When the driving means 3 displaces the lifting beam 1
telescopically out of the lifting beam 2, the pressure spring 5
will press the casing 4 upwards to the position shown in FIG. 2.
The power of the pressure spring 5 can be so adapted that the
casing 4 will cover as much of the lifting beam 1 as of the lifting
beam 2 when the lifting beam 1 is in its most protruded position.
However, it can alternatively be so arranged that the casing 4 in
its lower end, that is to say the end which is closest to the
lifting means, is a ring 8 which will rest against the support 6
when the casing 4 is in the position shown in FIG. 2 by being
displaced by the pressure spring 5. The length of the casing 4
shall advisably be half of the lifting beam 1 plus half of the
lifting beam 2 as shown in FIG. 2. The ring 8 also acts as a
support between the casing 4 and the lifting arm 2, and the cover 7
on the casing 4 is designed to act in the same way in relation to
the lifting beam 1. In the position of the lifting beams shown in
FIG. 2, the casing 4 will take up bending forces on the lifting
beams specifically within the area where the lifting beam 2 is
telescopically protruded out of the lifting beam 2.
[0014] FIG. 3 shows a part of a longitudinal cross section at the
area A in FIG. 1. This figure shows the support 6 which is attached
to the casing against which the lower end of the pressure spring is
resting.
[0015] FIG. 4 shows a longitudinal cross section of the lower part
of the casing in the position B in FIG. 2. In this position the
casing has been displaced by the pressure spring 5 so far as
possible by that the pressure spring 5 has carried out a pressure
between the support 6 and the cover 7 of the casing 4. Also, the
support ring 8 is shown, which forms a support between the lifting
beam 2 and the casing 4. The ring may also form a limitation for
how far the casing 4 can be displaced upwards on the lifting beam 2
by that the support 6 will come to rest on the ring 8. The support
6 is thus firmly attached to the inner side of the casing 4.
[0016] FIG. 5 shows a longitudinal cross section of the upper part
of the casing 4 at a position C in FIG. 2. It is hereby seen that
the pressure spring 5 rests on the cover 7 attached at the upper
end of the casing 4.
[0017] There are alternative solutions within the scope of the
invention as for instance the design of the supports, the design of
the cover and also the design of the support ring. The support ring
may be omitted by that the outer dimension of the lifting arm 2 is
adapted to the inner dimension of the casing in an area below the
pressure spring 5, that is to say in the area B according to FIG.
2. The upper end of the casing can be designed in another way and
have a design similar to a ring instead of a cover. It should also
be noted that in the foregoing disclosure two lifting beams have
been described but the inventive idea also includes several lifting
beams arranged one after the other.
* * * * *